藏红花酸对链脲佐菌素诱导的糖尿病大鼠视网膜神经上皮的保护作用

目的研究藏红花酸对链脲佐菌素(Streptozotocin,STZ)诱导的糖尿病大鼠视网膜神经上皮的保护作用及机制。方法♂SD大鼠40只,随机选取30只腹腔注入STZ(60 mg·kg^-1)将大鼠随机分为3组:糖尿病对照组、藏红花酸低剂量组(50 mg·kg^-1·d^-1,p.o.)、藏红花酸高剂量组(100 mg·kg^-1·d^-1,p.o.)。空白对照组及糖尿病组每天给予3 mL 0.5%CMC-Na。第8周末取各组大鼠眼球检测视网膜神经上皮caspase-3、蛋白激酶C(protein kinase C,PKC)表达量,实时荧光定量PCR检测大鼠视网膜神经上皮Bcl-2、TNF-α、Bax、PKC-βmRNA表达水平。结果caspase-3、TNF-α、PKC及Bax表达量DM组表达最高,DM+CRO组比DM组明显下降(P<0.05),Bcl-2表达量DM+CRO处理组较DM组明显升高(P<0.01)。结论藏红花酸对STZ诱导的糖尿病大鼠视网膜神经上皮具有保护作用,其可能机制是抑制TNF-α、Bax、caspase-3表达,提高Bcl-2的表达,并且藏红花酸可以减少视网膜神经上皮PKC蛋白和基因的表达,保护糖尿病大鼠视网膜。

Protective effect of crocetin on retinal neuroepithelial in streptozotocin induced diabetic rat

Aim To detect the protective effect of cro-cetin on retinal neuroepithelial in streptozotocin in-duced diabetic rat and uncover the mechanism.Meth-ods Thirty rats were injected streptozotocin(60 mg·kg-1),rats were randomly divided into three groups:diabetic model(DM)group,crocetin low doseDM+CRO(L)]group(50 mg·kg^-1·d^-1,p.o.),croce-tin high doseDM+CRO(H)]group(100 mg·kg^-1·d^-1,p.o.),CON group and DM group were gave 3 mL 0.5%CMC-Na.In the end of eighth week,all rats were killed and took eye balls to detected the ex-pression level of caspase-3 by immunohistochemical,and the protein expression levels of protein kinase C(PKC),and the mRNA expression levels of Bcl-2,TNF-α,PKC-βby quantitative realtime fluorescence polymerase chain reaction(qRT-PCR).Results caspase-3,TNF-α,PKC and Bax expression in DM+CRO group was significantly lower than DM group(P<0.05),the Bcl-2 expression of DM+CRO were signif-icantly higher than DM group(P<0.01).Conclusion Crocetin has protective effect on retinal neuroepithe-lial in streptozotocin induced diabetic rat.It can de-crease the expressing level of caspase-3,TNF-αand Bax and increasing the level of Bcl-2.Also crocetin re-duce the expression of PKC then leading a protective effect in retinal neuroepithelial cells.